CBCS Collections attempting to collect invalid debt Columbus Ohio

I received a suspicious letter in the mail from CBCS saying that they were attempting to collect money on behalf of Riverside Methodist Hospital. This was surprising because i had not been to that hospital in many years. I had not recieved any previous bills from them or any other healthcare provider for that matter. What's even more suspicious is that they say i owe $62.75 but that if I respond in 30 day or less they'll settle for 50% of that amount. I know it's not much money but it's the principal of the matter, I was unaware of any debt and refuse to just shell out money to anyone who asks for it.

Anyway I went to their website and found only one contact email address, what follows is the email i sent:

To whom it may concern,
I received a bill in the mail from your company asking me to settle the account with your client, Riverside Methodist Hospital, within 30 days for $31.38 or pay $62.75. I'm a little confused though because I've never heard of your company and thus would be very surprised to learn that I have a legitimate account. Also, since I have not been to Riverside in many years my suspicion that this is some kind of error is only further advanced. After reading your letter I am now contacting you because I absolutely and wholeheartedly "...dispute the validity of this debt...". If you can provide proof that I, in fact do owe money for services rendered then I will settle the account. However, I implore you to take notice that I do not use the word "proof" lightly. The burden of proof is on your shoulders, and I await your response.

Foxm
Columbus, Ohio
U.S.A.